Pennsylvania class E3
United States 1903 178 produced
The E3 was an Atlantic that was built by the PRR parallel to its E2 that was largely similar, but had larger cylinders. Between 1901 and 1910, a total of eight E3, 114 E3a and 56 E3d were built in the Juniata shops at Altoona. With 80 inch drivers they could not produce a high tractive effort, but with the introduction of steel passenger cars this was offset by operating them double-headed.
After the more powerful E6 Atlantics had been introduced, the E2 and E3 were called “Light Atlantics”. Beginning in 1912 they were superheated and their boiler pressure was reduced from 205 to 195 psi. In this process, a total of 90 E2a, E2d, E3a and E3d became the E3sd. They were used until the thirties and all were scrapped.
Technical data
General
| Property | E3a | rebuilt E3sd |
|---|---|---|
| Built | 1903-1905 | 1912-1914 |
| Manufacturers | Altoona | |
| Wheel arrangement | 4-4-2 (Atlantic) | |
| Gauge | 1,435 mm (Standard gauge) | |
Dimensions and weights
| Property | E3a | rebuilt E3sd |
|---|---|---|
| Wheelbase | 9.39 m | |
| Total wheelbase | 18.35 m | 18.45 m |
| Service mass | 86.2 t | 94.7 t |
| Adhesion mass | 53.7 t | 58.5 t |
| Total mass | 147.4 t | 163.6 t |
| Rigid wheelbase | 2.26 m | |
| Axle load | 28 t | 30.6 t |
| Water capacity | 21,955 l | |
| Fuel capacity | 11.8 t (coal) | 12.7 t (coal) |
Boiler
| Property | E3a | rebuilt E3sd |
|---|---|---|
| Grate area | 5.156 m² | |
| Firebox surface | 15.394 m² | 17.373 m² |
| Tube heating surface | 229.777 m² | 172.242 m² |
| Evaporative heating surface | 245.171 m² | 189.615 m² |
| Total heating surface | 245.2 m² | 227.9 m² |
| Superheater surface | 38.276 m² | |
Power plant
| Property | E3a | rebuilt E3sd |
|---|---|---|
| Driver diameter | 2,032 mm | |
| Boiler pressure | 14.1 bar | 13.4 bar |
| Expansion type | simple expansion | |
| Cylinders | two, 559 x 660 mm | |
Power
| Property | E3a | rebuilt E3sd |
|---|---|---|
| Power source | steam | |
| Estimated power | 1,193 kW (1,622 PS) | 1,268 kW (1,724 PS) |
| Starting effort | 121.9 kN | 116.0 kN |
Calculated values
| Property | E3a | rebuilt E3sd |
|---|---|---|
| Factor of adhesion | 1 : 4.32 | 1 : 4.95 |
| Optimal speed | 60 km/h | 68 km/h |
| Power-to-weight ratio | 13.8 kW/t | 13.4 kW/t |
| Heating Surface Equivalent | 322.1 m² | 353.0 m² |
| Cylinder volume/HSE | 1 : 1,005.53 | 1 : 917.54 |
| Adhesive weight/Total | 1 : 1.60 | 1 : 1.62 |
| Tractive force/Heating surface | 1 : 10.39 | 1 : 10.63 |
| Grate area/Heating surface | 1 : 47.55 | 1 : 44.20 |
| Firebox/Tube surface | 1 : 14.93 | 1 : 9.91 |
| Total/Superheater | 1 : 4.95 |
